Hello Thomas Hellstrom,
The patch fb80edb0d766: "drm/vmwgfx: Implement an infrastructure for read-coherent resources" from Mar 28, 2019, leads to the following static checker warning:
drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c:461 vmw_bo_vm_fault() warn: missing conversion: 'page_offset + ((1) << 12)' 'page + byte'
drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c:534 vmw_bo_vm_huge_fault() warn: missing conversion: 'page_offset + ((1) << 12)' 'page + byte'
drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c 435 vm_fault_t vmw_bo_vm_fault(struct vm_fault *vmf) 436 { 437 struct vm_area_struct *vma = vmf->vma; 438 struct ttm_buffer_object *bo = (struct ttm_buffer_object *) 439 vma->vm_private_data; 440 struct vmw_buffer_object *vbo = 441 container_of(bo, struct vmw_buffer_object, base); 442 pgoff_t num_prefault; 443 pgprot_t prot; 444 vm_fault_t ret; 445 446 ret = ttm_bo_vm_reserve(bo, vmf); 447 if (ret) 448 return ret; 449 450 num_prefault = (vma->vm_flags & VM_RAND_READ) ? 1 : 451 TTM_BO_VM_NUM_PREFAULT; 452 453 if (vbo->dirty) { 454 pgoff_t allowed_prefault; 455 unsigned long page_offset; 456 457 page_offset = vmf->pgoff - 458 drm_vma_node_start(&bo->base.vma_node); 459 if (page_offset >= bo->resource->num_pages || ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ page_offset is in terms of pages
460 vmw_resources_clean(vbo, page_offset, --> 461 page_offset + PAGE_SIZE, ^^^^^^^^^^^^^^^^^^^^^^^ It doesn't make sense to add PAGE_SIZE (which is bytes) to pages. The code in vmw_bo_vm_huge_fault() has a similar bug.
462 &allowed_prefault)) { 463 ret = VM_FAULT_SIGBUS; 464 goto out_unlock; 465 } 466 467 num_prefault = min(num_prefault, allowed_prefault); 468 } 469 470 /* 471 * If we don't track dirty using the MKWRITE method, make sure 472 * sure the page protection is write-enabled so we don't get 473 * a lot of unnecessary write faults. 474 */ 475 if (vbo->dirty && vbo->dirty->method == VMW_BO_DIRTY_MKWRITE) 476 prot = vm_get_page_prot(vma->vm_flags & ~VM_SHARED); 477 else 478 prot = vm_get_page_prot(vma->vm_flags); 479 480 ret = ttm_bo_vm_fault_reserved(vmf, prot, num_prefault, 1); 481 if (ret == VM_FAULT_RETRY && !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) 482 return ret; 483 484 out_unlock: 485 dma_resv_unlock(bo->base.resv); 486 487 return ret; 488 }
regards, dan carpenter